A conventional shift range control apparatus switches over a shift range by controlling a motor of a shift range switchover device in response to a shift range switchover request from a driver. For example, in a shift range switchover device disclosed in JP 2004-308848A, a switched reluctance motor (SR motor) is used as a motor as a drive power source. The SR motor, which does not use permanent magnets, is simple in structure.
A driven torque of the SR motor is, however, small, when no power is supplied. For this reason, in the shift range switchover device, when power supply to the SR motor is stopped under a state that a roller of a detent spring provided as a detent mechanism is located near a center of a recessed part of the detent plate, the roller is easily placed in position in the center of the recessed part of the roller by a pushing force of the detent spring. Thus the detent plate is placed in position relatively easily.
A motor such as a DC brushless motor, which uses permanent magnets, has a better response characteristic than the SR motor but its driven torque under no power supply is larger. For example, the SR motor of the shift range switchover device is replaced with a DC motor, it is possible to improve the response characteristic but probably not possible to place the roller in position to the recessed part by the pushing force of the detent spring when the power supply to the motor is stopped under the state that the roller of the detent spring is near the recessed part of the detent plate. As a result, the detent plate is likely to be not positioned with high accuracy.